Seasonal, spatial and multi-annual dynamics of phosphorus forms in bottom sediments and their interstitial water for river Dniester was evaluated. The spatial dynamics of phosphorus forms in the bottom sediments along river had, in general, the same trend during of 2004 and 2009 years, being recorded the increasing tendency along river Dniester for inorganic phosphorus and decreasing tendency for organic phosphorus. Multi-annual dynamics for 2004-2010 years showed a tendency of increasing of all phosphorus forms in bottom sediments; the highest values being registered during 2010 year. Spatial and seasonal dynamics of phosphorus forms in bottom sediments and their interstitial water were generally in correspondence, although sometimes with some differences.